The town`s air was consistently _____: depending on the breeze, one might be greeted with the sour effluvia of twenty breweries, choking fumes from the coal factory, or brackish smells from the nearby river.
Scientist reported last month on a sign of relative solar _____; the solar wind, a rush of charged particles continually spewed from the Sun at a million miles an hour, had diminished to its lowest level in 50 years.
An Irish newspaper editorial encouraging women to participate in the non-importation movement launched in Ireland in 1779 appears consistent with a perception that the political use of the consumer boycott originated in North America and spread eastwards across the Atlantic to Ireland. This is a view that most historians have concurred with. For example, T.H. Breen argued that the consumer boycott was a brilliantly original American invention. Breen did acknowledge that a few isolated boycotts may have taken place in other countries. However, Mary O'Dowd argues that from the late seventeenth century, Irish political discourse advocated for the nonconsumption of imported goods and support for home manufactures by women in ways that were strikingly similar to those used later in North America.
In 1995 the Galileo spacecraft captured data about Jupiters atmosphere-namely, the absence of most of the predicted atmospheric water-that challenged prevailing theories about Jupiters structure. The unexpectedness of this finding fits a larger pattern in which theories about planetary composition and dynamics have failed to predict the realities discovered through space exploration. Instead of normal planets whose composition could be predicted by theory, the planets populating our solar system are unique individuals whose chemical and tectonic identities were created through numerous contingent events. One implication of this is that although the universe undoubtedly holds other planetary systems, the duplication of the sequence that produced our solar system and the development of life on Earth is highly unlikely.

Recently planetary scientists have suggested that the external preconditions for the development of Earth`s biosphere probably included four paramount contingencies. First, a climate conducive to life on Earth depends upon the extraordinarily narrow orbital parameters that define a continuously habitable zone where water can exist in a liquid state. If Earths orbit were only 5 percent smaller than it is, temperatures during the early stages of Earths history would have been high enough to vaporize the oceans. If the Earth-Sun distance were as little as 1 percent larger, runaway glaciation on Earth about 2 billion years ago would have caused the oceans to freeze and remain frozen to this day. Second, Jupiter`s enormous mass prevents most Sun-bound comets from penetrating the inner solar system. It has been estimated that without this shield, Earth would have experienced bombardment by comet-sized impactors a thousand times more frequently than has actually been recorded during geological time. Even if Earth`s surface were not actually sterilized by this bombardment, it is unlikely that any but the most primitive life-forms could have survived. This suggests that only planetary systems containing both terrestrial planets like Earth and gas giants like Jupiter might be capable of sustaining complex life-forms.

Third, the gravitational shield of the giant outer planets, while highly efficient, must occasionally fail to protect Earth. Paradoxically, while the temperatures required for liquid water exist only in the inner solar system, the key building blocks of life, including water itself, occur primarily beyond the asteroid belt. Thus the evolution of life has depended on a frequency of cometary impacts sufficient to convey water, as well as carbon and nitrogen, from these distant regions of the solar system to Earth while stopping short of an impact magnitude that would destroy the atmosphere and oceans.

Finally, Earth`s unique and massive satellite, the Moon, plays a crucial role in stabilizing the obliquity of Earth`s rotational axis, this obliquity creates the terrestrial seasonality so important to the evolution and diversity of life. Mars, in contrast, has a wildly oscillating tilt and chaotic seasonality, while Venus, rotating slowly backward, has virtually no seasonality at all.
The passage is primarily concerned with
Our terrestrial food supply comes from ecosystems transformed to produce a few comestible species through the removal of competitors, predators, and pests, but marine capture fisheries depend on the overall productivity of natural ecosystems. There is, however, increasing concern about the impact of fishing and other human activities on marine ecosystems, which are now far from pristine. One option for moving toward both biodiversity and terrestrial food supply goals is to produce greater yields from less land, thereby freeing land for conservation purposes. By contrast, the objective of maintaining or resorting the biodiversity of marine ecosystems may conflict with the objective of maintaining or increasing our food supply from the sea, since the level of fishing required to achieve the latter may compromise the former.
In 1755 British writer Samuel Johnson published an acerbic letter to Lord Chesterfield rebuking his patron for neglect and declining further support. Johnson`s rejection of his patron`s belated assistance has often been identified as a key moment in the history of publishing, marking the end of the culture of patronage. However, patronage had been in decline for 50 years, yet would survive, in attenuated form, for another 50. Indeed, Johnson was in 1762 awarded a pension by the Crown-a subtle form of sponsorship, tantamount to state patronage. The importance of Johnson`s letter is not so much historical as emotional; it would become a touchstone for all who repudiated patrons and for all who embraced the laws of the marketplace.
Various factors complicate researchers` efforts to study time spent on housework. For example, housework may not stand out much in respondents` memories because it is so (i)_______ everyday life, and (ii)______ problems among survey subjects may thus be more severe than for other activities.
Building the first United States transcontinental phone line required fundamental innovations: for example, engineers created an amplifier for the electric signals to prevent them from ______ after a few miles.
Computerized facial-recognition systems can be ________ by any number of factors, from the dirt caked on a camera lens to a hat pulled low over a subject`s face.
Globally, the combination of reforestation and afforestation activities could reduce atmosphere CO2 concentrations by as much as 30 parts per million (ppm) this century. However, this potential mitigation is limited by many factors. One is the vulnerability of forests to increased disturbances, including those caused by pathogens, droughts, fires, and storms. For example, the mountain pine beetle is projected to convert 374,000 square kilometers (km2) of pine forest from a small net carbon sink to a large carbon source in Alberta alone, liberating 1 billion tons of CO2 into the atmosphere. Climate change is another factor that could limit the potential for carbon sequestration in forests. The mountain pine beetle in Alberta is thriving in part because of warmer minimum temperatures in the winter and warmer and drier summers. A third potential limitation is landowner behavior in private-sector forestry, including decisions on what species to plant and how intensely to manage forests. Private forestry competes economically with agriculture, urban development, and other land uses. Landowner decisions will therefore dictate the success of some climate policy efforts.
Science is arguably a very high-minded pursuit, but that is not to say that all of its practitioners are _____, as numerous articles alleging overly generous pharmaceutical industry payments to medical researchers have tried to show.
Amy and Jed are armong the 35 people, who are standing in a line, one behind the other, waiting to buy movie tickets. The number of people in front of Amy plus the number of people behind Jed is 24. If there are 15 people behind Amy, including Jed, how many people are in front of Jed?
The integer n is the product of five consecutive positive integers. Which of the following integers must be a factor of n?

Indicate all such numbers.

Quantity A


Quantity B


There are four books A, B, C, and D, how many arrangements if A and B must be next to each other?
Two librarians, Robert and Patricia,cataloged a combined total of 180 new books,each of which was cataloged by only one of the two librarians. Although they spent the same amount of time cataloging their books, Robert spent an average of 15 minutes per book whereas Patricia spent an average of 12 minutes per book.

Quantity A

The number of books cataloged by Robert

Quantity B


Quantity A

The sum of interior angles of a pentagon plus 90°

Quantity B

The sum of interior angles of a hexagon

Quantity A

The perimeter of ABCD

Quantity B

The sum of the lengths of diagonals AC and BD


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